Allow for manual refresh with ^R

[bcongdon]

It would be nice to be able to manually refresh the markdown render.

Use case: I use grip to preview my markdown, and run grip with --norefresh (I was hitting up against the Github API limit). It would be nice to be able to do a ^R (or whatever) in the console and manually regenerate the markdown (Jekyll has functionality similar to this)

I'm willing to make the changes in a PR, so I just want a signal as to if this would be something acceptable by the authors.

[joeyespo]

Even though Jekyll does this, I'm not convinced it's actually a good feature.

Grip is a CLI app that runs a server and prints its output (until a stop signal is received somehow). All interaction takes place at the HTTP request level, whereas the terminal is a one-way channel (aside from the standard "terminate signal" handling). Handling bidirectional communication at that level will complect the system and its design. (How would cat README.md | grip - work? Grip would have to become a bit more aware of the environment its run in.)

Since the underlying problem is the rate limit, there's two other things you can do here:

• Increase the limit by using a GitHub access token
• Refresh in the browser (A little slower, yeah, but tabbing between your editor, the terminal, and the browser has its own variant of slowness. The request to GitHub is the real bottleneck.)

Adding ^R is just patching the symptom. On the other hand, the offline renderer (#35) would solve this for good. So I'd rather focus energy on that.

Thanks for the suggestion, @bcongdon!